This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The project aims to determine the biodistribution of polymeric nanocomplexes labeled with quantum dots, following oral administration in a closed intestinal loop model. As a pilot study, quantum dots that emit in the far-red region will be used to label DNA, which is then used to form nanocomplexes with chitosan. The nanoparticles are then administered to isolated sections of rat gastrointestinal tract (GIT) for pre-determined durations. Following the excision of the relevant sections of the GIT, we propose to determine the uptake of the nanocomplexes by means of the Kodak In-Vivo Imaging System. The system would provide a semi-quantitative identification of the specific sections of the GIT that show enhanced uptake of our nanocomplexes. Such a study would enable us to better design polymeric gene carriers and macroformulations that would further protect the DNA and nanocomplexesin order to facilitate more efficient oral gene delivery.